Articles | Volume 11, issue 8
https://doi.org/10.5194/wes-11-2987-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wes-11-2987-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Controlling rigid-wing airborne wind energy systems during circular flight without exact path following
School of Civil, Aerospace, and Design Engineering, University of Bristol, Bristol, BS8 1TR, United Kingdom
Agustí Porta Ko
Kitemill AS, Voss, 5704, Norway
Technical University of Denmark, Frederiksborgvej 399, 4000 Roskilde, Denmark
Tallak Tveide
Kitemill AS, Voss, 5704, Norway
Mark H. Lowenberg
School of Civil, Aerospace, and Design Engineering, University of Bristol, Bristol, BS8 1TR, United Kingdom
Espen Oland
Kitemill AS, Voss, 5704, Norway
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Measuring atmospheric turbulence high above the ground is complex, as masts are too short and remote-sensing devices lose accuracy with height. This study shows that a tethered flying kite, already used to harvest wind energy at high altitudes, can also act as a turbulence sensor using standard onboard instruments. A method is proposed to obtain relevant turbulence parameters, some unavailable to conventional instruments, helping fill a measurement gap.
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Airborne wind energy systems (AWESs) are an emerging technology for power generation using tethered aircraft. The flight dynamics characteristics of rigid-wing AWESs in circular flight is discussed. We examine the cyclic control input to achieve circular soaring flight while being tethered. It was also found that large-radius circular orbits are unstable. The insights gained from this research can help to inform future control design for rigid-wing AWES.
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Airborne wind energy could produce more electricity by flying where winds are stronger and adjusting the wing as conditions change. Using detailed computer simulations, we found that a simple automatic flap adjustment increased average power by 47 %. Together, adjusting the flaps and raising the flight path increased it by 71 %. The path’s shape mattered little, but its height and size did. These findings offer practical ways to improve power without making flight less stable.
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Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2026-150, https://doi.org/10.5194/wes-2026-150, 2026
Preprint under review for WES
Short summary
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Measuring atmospheric turbulence high above the ground is complex, as masts are too short and remote-sensing devices lose accuracy with height. This study shows that a tethered flying kite, already used to harvest wind energy at high altitudes, can also act as a turbulence sensor using standard onboard instruments. A method is proposed to obtain relevant turbulence parameters, some unavailable to conventional instruments, helping fill a measurement gap.
Duc H. Nguyen, Mark H. Lowenberg, and Espen Oland
Wind Energ. Sci., 11, 285–298, https://doi.org/10.5194/wes-11-285-2026, https://doi.org/10.5194/wes-11-285-2026, 2026
Short summary
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Airborne wind energy systems (AWESs) are an emerging technology for power generation using tethered aircraft. The flight dynamics characteristics of rigid-wing AWESs in circular flight is discussed. We examine the cyclic control input to achieve circular soaring flight while being tethered. It was also found that large-radius circular orbits are unstable. The insights gained from this research can help to inform future control design for rigid-wing AWES.
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Short summary
A new flight control architecture for airborne wind energy systems is proposed for circular-pattern flight during the power production phase. The controller 'wraps' around a reference cylinder and thereby does not require exact path planning or waypoint-based navigation. This simple guidance method enables the controller to function with only proportional-integral regulators. Further extensions to the controller enable flying with near-constant angle of attack and multi-kite synchronisation.
A new flight control architecture for airborne wind energy systems is proposed for...
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